title: Hepatocellular carcinoma with foamy histiocyte-like appearance: a deceptively clear cell carcinoma appearing variant.
abstract: Hepatocellular carcinoma (HCC) shows many pathological features, and it varies architecturally and cytologically. There have been many reports and discussions of the morphological features of HCC. A 63-year-old man was found to have a solitary tumor in liver segment 7 that was diagnosed as HCC. A partial resection of liver segment 7 was performed. Microscopically, the tumor lesion showed a moderately differentiated HCC. There was also a lesion with foamy histiocyte-like cells corresponding to the white lesion in the face of the cut tumor. Immunohistochemical staining showed that they were negative for CD68, S-100, vimentin, and HMB-45. The cytoplasm itself was negative on periodic acid Schiff (PAS) and Sudan staining. Without immunohistological analysis, it is difficult to distinguish this HCC variant from clear cell carcinoma or metastases of renal cell carcinoma. It is important to recognize this type as a specific cytological variant of HCC that requires confirmation by immunohistochemistry. This report describes the case of a patient with a morphologically distinctive pattern of HCC with prominent cell cytoplasm that had a foamy histiocyte-like appearance. To the best of our knowledge, this is the first report of this HCC variant.
authors.affiliation: Department of Hepatobiliary Pancreatic Surgery, National Cancer Center Hospital East, Kashiwa, Japan.
authors.forename: Takuji
authors.initials: T
authors.lastname: Noro
authors.forename: Naoto
authors.initials: N
authors.lastname: Gotohda
authors.forename: Motohiro
authors.initials: M
authors.lastname: Kojima
authors.forename: Masaru
authors.initials: M
authors.lastname: Konishi
authors.forename: Toshio
authors.initials: T
authors.lastname: Nakaghori
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Takahashi
authors.forename: Takayuki
authors.initials: T
authors.lastname: Hasebe
authors.forename: Taira
authors.initials: T
authors.lastname: Kinoshita